[Characterization and inheritance of resistance to stripe rust in the wheat line Guinong775]

Exploring different types of resistance genes and deploying diversity resistance genes among different wheat producing regions are important strategy to control stripe rust epidemic in large scale. The resistance spectra of the wheat line Guinong 775 at seedling stage was tested in greenhouse with ten isolates of Puccinia triticina West. f. sp. tritici; and the inheritance of resistance was investigate with F(2:3) and BC(1) populations derived from a cross between Guinong 775 and a susceptible cultivar Avocet (S), inoculated with isolates CYR32 and CH42, which poses a notable threat to current wheat varieties carrying Yr26 resistance gene. The results showed that Guinong 775 was immune or nearly immune to all the tested races; however, the resistant germplasm 92R137, Chuanmai 42, Guinong 22, and Yr24/6*Avocet (S) were susceptible to CH42. The resistance of Guinong 775 was conferred by a single dominant gene to CYR32 and another single dominant gene to CH42, and these genes proved to be different.